Recovery of oil from tar sands using water-external micellar dispersions

ABSTRACT

Oil from tar sands is recovered by contacting the tar sands with a water-external micellar dispersion in amounts sufficient to solubilize at least portions of the oil from the tar sands. Thereafter, the solubilized oil within the micellar dispersion is separated from the &#39;&#39;&#39;&#39;spent&#39;&#39;&#39;&#39; tar sands and the oil is recovered from the micellar dispersion. To facilitate the solubilization, the micellar dispersion can have a pH of about 7-14 and the micellar dispersion and/or the tar sand can be heated to temperatures above 100* F. Volume amounts of about 0.05 to about 30 volumes of micellar dispersion per volume of tar sand is useful with the invention. The micellar dispersion contains hydrocarbon, surfactant, aqueous medium, and optionally cosurfactant and/or electrolyte.

United States Patent Keely, deceased et al.

14 1 Feb. 22, 1972 [72] Inventors: .Ioe T. Keely, deceased, late of Littleton, C010. by LaVeme S. Kelly, executrix; Fred H. Poettlnan, Littleton, C010.

[73] Assignee: MarathonO'IlCompany, Findlay, Ohio [22] Filed: Dec. 29, 1969 [21] App1.No.: 888,899

[52] ..208/11 [51] Int.Cl............... [58] FieldofSearch ..208I11 [56] References Cited UNITED STATES PATENTS 2,921,010 1/1960 Sherbome ..208l11 3,542,666 11/1970 Simpson ..208I11 2,911,349 11/1959 Coulson ..208/11 Canevari et a1 ..208/11 Poettmann et a1 ..208l1 1 Primary Examiner-Curtis R. Davis Attorney-Joseph C. Herring, Richard C. Willson, Jr. and Jack L. Hummel ABSTRACT Oil from tar sands is recovered by contacting the tar sands with a water-external micellar dispersion in amounts sufi'icient to solubilize at least portions of the oil from the tar sands. Thereafter, the solubilized oil within the micellar dispersion is separated from the spent" tar sands and the oil is recovered from the micellar dispersion. To facilitate the solubilization, the micellar dispersion can have a pH of about 7-14 and the micellar dispersion and/or the tar sand can be heated to temperatures above 100 F. Volume amounts of about 0.05 to about 30 volumes of micellar dispersion per volume of tar sand is useful with the invention. The micellar dispersion contains hydrocarbon, surfactant, aqueous medium, and optionally cosurfactant and/or electrolyte.

15 Claims, No Drawings RECOVERY OF OIL FROM TAR SANDS USING WATER- EXTERNAL MICELLAR DISPERSIONS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to the recovery of hydrocarbon from mined tar sands by contacting the sands on the surface with a water-external micellar dispersion to solubilize the hydrocar bon from the tar sands, thereafier the micellar dispersion con taining the solubilized hydrocarbon is separated from the tar sands, and then the solubilized hydrocarbon is recovered from the micellar dispersion. The micellar dispersion contains hydrocarbon, surfactant (preferably petroleum sulfonate), and an aqueous medium and optionally cosurfactant andlor electrolyte. Preferably, the tar sands are.comrninuted before being contacted with the water-extemal micellar dispersion.

2. Description of the Prior Art Tar sands, also known as oil sands, bituminous sands, etc, are sands which contain a very viscous oil or hydrocarbon. Large deposits are found throughout the world, e.g., Althabasca sands found in Northern Alberta, Canada. Tar sands usually have an asphaltic appearance due to the very viscous hydrocarbon within the sand. The viscosity of the hydrocarbon is substantially more viscous than the average crude oil produced by the majority of our petroleum technology. Therefore, the technology used to produce the lower viscosity crude oil is generally not applicable to the production of oil from the tar sands.

U.S. Pat No. 1,497,607 to Streppel teaches the recovery of oil from tar sands by separating oil from tar sand with the aid of steam. Thereafter, the oil, due to its lower specific gravity, forms a layer on top of water and is separated from the sands.

U.S. Pat. No. 2,9 I 0,242 to Tek et al. teaches the recovery of oil from tar sands by subjecting a suspension or slurry of the sands to centrifugal forces generated in a hydraulic cyclone. For example, the sand is comminuted, mixed with water (can optionally contain surfactant), and then pumped into a hydraulic cyclone separator. Such produces centrifugal forces in excess of gravity whereby a vortex is formed within the cyclone and the sand is separated from the oil.

U.S. Pat. No. 3,050,289 to Gerner teaches the recovery of oil from tar sands by leaching the tar sands from a pit using a hydrocarbon solvent (can be heated to 200 F.) and then taking the hydrocarbon-soaked tar sands and transferring them to a kiln wherein superheated steam (up to 700 F.) is used to separate the oil from the tar sands. From the kiln, the aqueous vapor containing the hydrocarbon solvent and the oil extracted from the tar sands is sent to a fractionator wherein the solvent and condensed steam is separated from the oil.

SUMMARY OF THE INVENTION Applicants have discovered that oil within tar sands can be recovered by contacting the tar sands, preferably comminuted, with a watebexternal micellar dispersion in amounts sufficient to solubilize economically feasible portions of the oil from the tar sands. Thereafter, the micellar dispersion containing the solubilized oil is separated from the "spent" tar sand and subsequently the oil is recovered. The water-external micellar dispersion is preferably at a pH of about 7-14, preferably about l2 and also can be at temperatures in excess of F. and preferably l50 F. or more. Volume amounts of from about 0.05 to 30 volumes of the micellar dispersion per volume of tar sand is useful with the invention. Standard chemical engineering methods can be used to separate the micellar solution (containing solubilized oil) from spent tar sands and thereafter standard procedures can be used to recover the oil.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The water-external micellar dispersion useful in this inven tion is comprised of hydrocarbon, surfactant, aqueous medium, and optionally cosurfactant and/or electrolyte. Examples of volume amounts include about I percent to about 50 percent hydrocarbon, about 40 percent to about percent aqueous medium, at least about 4 percent surfactant, about 0.0l percent to about 20 percent or more of cosurfactant, and about 0.001 percent to about 5 percent by weight of electrolyte. In addition, the dispersion can contain other additives such as corrosion inhibiting agents, bactericides, sequestering agents, etc.

The hydrocarbon can be crude oil, partially refined fractions of crude oil. or refined fractions of crude oil. Specific examples include side cuts from crude oils, crude column overheads, gas oils, kerosenes, heavy naphthas, naphthas, straight run gasoline, liquefied petroleum gases, etc. Also, synthesized hydrocarbons are useful. In addition, the unsulfonated hydrocarbon within petroleum sulfonates is useful as the hydrocarbon.

The aqueous medium can be soft, brackish, or a brine water. Where the aqueous medium does contain ions, it is preferably compatible with the ions within the tar sands.

The surfactants useful with the micellar dispersion can be nonionic, cationic, and anionic surfactants. Specific examples of useful surfactants include those found in U.S. Pat. No. 3,254,7l4 to Gogarty et al. Also useful are surfactants like Duponol WAQE (a 30 percent active sodium lauryl sulfate marketed by DuPont Chemical Corp., Wilmington, Del.), Energetic W-l00 (a polyoxyethylene alkylphenol, marketed by Amour Chemical Co., Chicago, Ill), Triton X-l00 (a polyoxyethylene alkylphenol, marketed by Rohm 8L Haas, Philadelphia, Pa.), Arquad 12-50 (a 50 percent active dodecyl trimethyl ammonium chloride marketed by Armour Chemical Co., Chicago, Ill.), and like materials. Preferably, the surfactant is a petroleum sulfonate, also known as alkylaryl napthhenic sulfonate. Examples of useful sulfonates include monovalent cation containingsulfonates having an average equivalent weight within the range of about 350 to about $20 and more preferably about 400 to about 475. The surfactant can be a mixture of low, medium, and high average equivalent weight sulfonates or surfactants or mixtures of two or more different types of surfactants.

The cosurfactant can have limited water solubility and preferably has a water solubility of about 0.0l percent to about 20 percent at ambient temperature. However, cosurfactants having infinite water solubility are also useful. Specific examples of useful cosurfactant include alcohols, amino compounds, esters, aldehydes, ketones, and like materials containing from one to about 20 or more carbon atoms, and more preferably about three to about l6 carbon atoms. Useful examples include isopropanol, nand isobutanol, amyl alcohols such as n-arnyl alcohol, land Z-hexanol, land 2-octanol, decyl alcohols, alkaryl alcohols such as p-nonyl phenol, alcoholic liquors such as fusel oils, etc. Primary, secondary and tertiary alcohols are all useful. The concentration of the cosurfactant is preferably about 0.01 percent to about 5 percent by volume and more preferably about 0.01 percent to about 3 percent by volume. Mixtures of two or more different cosurfactants are useful.

The electrolyte useful with the water-external micellar dispersion include inorganic salts, inorganic acids, inorganic bases, organic salts, organic acids, and organic bases which are strongly or weakly ionized. Preferably the electrolyte is an inorganic base or inorganic salt, e. g., sodium hydroxide, sodium chloride, sodium sulfate, sodium nitrate, ammonium chloride, ammonium hydroxide, potassium chloride, etc. Examples of specific electrolytes useful with the invention include those found in US. Pat. No. 3,330,343 to Tosch el al. Where a high pH is desired, the electrolyte is preferably sodium hydroxide, ammonium hydroxide, and like materials.

Specific examples of useful water-extemal micellar dispersions are found in U.S. Pat. Nos. 3,506,070 and 3,506,07l to Jones.

The tar sand is preferably comminuted before being contacted with the micellar dispersion. This aids in more efficient contact of the available oil within the tar sand and thus increases the efficiency of solubilization of the oil by the micellar dispersion. Also, the tar sand can be heated to a high temperature, i.e., up to about above 100 F. and preferably 150 F., and greater,

The volume of micellar dispersion useful to contact the tar sands is about 0.05 to about 30 volumes and more preferably about 0.1 to about volumes of micellar dispersion per volume of tar sand. However, the economics of the particular situation and the desired return of investment will influence the most preferred volume ratios. in certain cases it may be desired to use an equal volume of the micellar dispersion per volume of tar sand. Also, side streams of the process can be recycled to a preferred location with the process to increase the solubilization efficiency.

When the tar sand is contacted with the micellar dispersion, it is preferred that mixing or agitation be present. This can be effected by mechanical agitators, flow patterns, etc. Also, increased temperatures in the mixing zone are preferred, temperatures up to the boiling point of the micellar dispersion are useful. For example, temperatures in excess of 100 F. and [50 F. are useful. Also, the pH of the micellar dispersion can be within the range of about 7 to about 14 and preferably about 12; such facilitates solubilization of the tar sands into the micellar dispersion. Side streams from the mixing zone can be removed and recycled back to desirable locations within the contacting phase to increase the solubilization efficiency. Also, side streams can be removed from the contacting phase and processed for recovery of the solubilized oil.

During the contacting phase, it is desired that the micellar dispersion be preheated to a temperature above about 100 F. and preferably above about 150 F. Where such high temperatures are desired, the components of the micellar dispersion are preferably selected to impart the higher thermostability range to the micellar dispersion. For example, higher molecular weight sulfonates and/or alcohols, increased molar ratios of surfactant to hydrocarbon, increased amounts of elec trolyte, increasing the aromaticity of the hydrocarbon, etc., are methods of increasing the thermostability range to higher temperatures. That is, at the higher temperatures, the micellar dispersion will not phase separate but possibly at lower temperatures the micellar dispersion may phase separate. Methods of increasing the thermostability range of the micellar dispersion are taught in US. Pat. Nos. 3,493,048 to Jones, 3,493,047 to Davis et al., 3,495,660 to Davis eta1., 3,500,912 to Davis et al. and 3,508,611 to Davis et al.

After the micellar dispersion has mixed sufficiently with the tar sands to solubilize at least portions of the oil out of the tar sands, the viscosity of the resulting mixture may be high, e.g., within the range of about 500-50000 cp. at ambient temperature. if such high viscosities are not desired in the process, such can be reduced by diluting the mixture with a low molecular weight hydrocarbon, e.g., kerosene, gasoline, etc., to obtain a lower viscosity, eg, viscosities of about 30-1,000 cp. at ambient temperature.

After the micellar dispersion has solubilized the oil out of the tar sands, the spent tar sands are separated from the mixture. This can be effected by classification, gravity separation, centrifugal separation, etc.

Thereafter, the micellar dispersion containing the solubilized oil is further processed to recover the oil from the micellar solution. in certain cases, especially where the micellar dispersion has been designed to have a high-temperature thermostability but does not have thermostability at lower temperatures, the temperature of the resulting mixture can be lowered to obtain phase separation; in this case the oil from the tar sands will be in the top phase. Where the latter occurs, the top phase can be decanted from the mixture to obtain the oil from the tar sands. The bottom phase, being mostly watersoluble components and some oil-soluble components, can be recycled back to the contacting stage and, before entering the contacting stage, it can be adjusted with the necessary and desired components to obtain a micellar dispersion having the desired thermostability range at the temperature used in the contacting step.

It is not intended that the invention be limited by the specifics taught herein. Rather, all equivalents obvious to those skilled in the art are intended to be incorporated within the scope of the invention as defined within the specification and appended claims.

What is claimed is:

l. A process of recovering oil from tar sands comprising contacting the tar sands with sufficient amounts of a water-external micellar dispersion comprised of hydrocarbon, surfactant, and aqueous medium to solubilize at least a portion of the oil from the tar sands, separating the sands from the micellar dispersion containing the solubilized oil, and then recovering the oil from the micellar dispersion.

2. The process of claim 1 wherein the micellar dispersion is at a temperature in excess of about 100 F.

3. The process of claim 1 wherein the water within the micellar dispersion has a pH within the range of about 7l4.

4. The process of claim 1 wherein the micellar dispersion is comprised of hydrocarbon, petroleum sulfonate, and aqueous medium.

5. The process of claim 4 wherein the micellar dispersion contains cosurfactant, electrolyte, or cosurfactant and electrolyte.

6. The process of claim 1 wherein from about 0.05 to about 30 volumes of the micellar dispersion per volume of tar sand is used in the process.

7. The process of claim I wherein the micellar dispersion is at a temperature in excess of 150 F.

8. The process of claim 1 wherein from about 0.1 to about 15 volumes of the micellar dispersion per volume of tar sand is used in the process.

9. The process of claim 1 wherein the micellar dispersion contains volume amounts of about l percent to about 50 percent hydrocarbon, about 40 percent to about percent aqueous medium, at least about 4 percent surfactant and optionally about 0.01 percent to about 20 percent cosurfactant and/or about 0.001 to about 5 percent by weight ofelectrolyte.

10. The process of claim 1 wherein sufficient hydrocarbon diluent is mixed with the micellar dispersion containing solubilized oil to lower the viscosity to about 30 to about L000 cp. at ambient temperature.

11. A process of recovering oil from tar sands comprising comminuting the tar sands, contacting the comminuted tar sands with about 0.05 to about 30 volumes of a micellar dispersion per volume of tar sands, the micellar dispersion comprised of about 1 percent to about 50 percent hydrocarbon, at least about 4 percent of a petroleum sulfonate having an average equivalent weight within the range of about 350 to about 520, and about 40 percent to about 95 percent aqueous medium, permitting the micellar dispersion to solubilize at least a portion of the oil from the tar sands, then separating the sands from the micellar dispersion containing the solubilized oil and thereafter recovering the oil from the micellar dispersron.

12. The process of claim 11 wherein the micellar dispersion is at a temperature in excess of F.

13. The process of claim 11 wherein the micellar dispersion contains about 0.01 percent to about 20 percent by volume of cosurfactant and about 0.001 percent to about 5 percent by weight of electrolyte.

14. The process of claim 11 wherein the pH of the micellar dispersion is within the range of about 7 to about l4.

15. The process of claim ll wherein sufficient hydrocarbon diluent is admixed with the micellar dispersion containing the solubilized oil to lower the viscosity of the micellar dispersion to about 30 to about 1,000 cp. at ambient temperature.

0 I i i 31 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Inventofls) Joe E KE i lX DGC'd et a1 ppears in the above-identified patent It is certified that error a hereby corrected as shown below:

and that. said Letters Patent are Inventor Joe T. Kelly's name is incorrectly shown as "Joe T. Keely" and is hereby corrected to read:

-J'oe T. Kelly, Deceased-- Signed and sealed this 6th day of June 1972.

(SEAL) Attest:

EDWARD M.FLETCHER, JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

2. The process of claim 1 wherein the micellar dispersion is at a temperature in excess of about 100* F.
 3. The process of claim 1 wherein the water within the micellar dispersion has a pH within the range of about 7-14.
 4. The process of claim 1 wherein the micellar dispersion is comprised of hydrocarbon, petroleum sulfonate, and aqueous medium.
 5. The process of claim 4 wherein the micellar dispersion contains cosurfactant, electrolyte, or cosurfactant and electrolyte.
 6. The process of claim 1 wherein from about 0.05 to about 30 volumes of the micellar dispersion per volume of tar sand is used in the process.
 7. The process of claim 1 wherein the micellar dispersion is at a temperature in excess of 150* F.
 8. The process of claim 1 wherein from about 0.1 to about 15 volumes of the micellar dispersion per volume of tar sand is used in the process.
 9. The process of claim 1 wherein the micellar dispersion contains volume amounts of about 1 percent to about 50 percent hydrocarbon, about 40 percent to about 95 percent aqueous medium, at least about 4 percent surfactant and optionally about 0.01 percent to about 20 percent cosurfactant and/or about 0.001 to about 5 percent by weight of electrolyte.
 10. The process of claim 1 wherein sufficient hydrocarbon diluent is mixed with the micellar dispersion containing solubilized oil to lower the viscosity to about 30 to about 1,000 cp. at ambient temperature.
 11. A process of recovering oil from tar sands comprising comminuting the tar sands, contacting the comminuted tar sands with about 0.05 to about 30 volumes of a micellar dispersion per volume of tar sands, the micellar dispersion comprised of about 1 percent to about 50 percent hydrocarbon, at least about 4 percent of a petroleum sulfonate having an average equivalent weight within the range of about 350 to about 520, and about 40 percent to about 95 percent aqueous medium, permitting the micellar dispersion to solubilize at least a portion of the oil from the tar sands, then separating the sands from the micellar dispersion containing the solubilized oil and thereafter recovering the oil from the micellar dispersion.
 12. The process of claim 11 wherein the micellar dispersion is at a temperature in excess of 100* F.
 13. The process of claim 11 wherein the micellar dispersion contains about 0.01 percent to about 20 percent by volume of cosurfactant and about 0.001 percent to about 5 percent by weight of electrolyte.
 14. The process of claim 11 wherein the pH of the micellar dispersion is within the range of about 7 to about
 14. 15. The process of claim 11 wherein sufficient hydrocarbon diluent is admixed with the micellar dispersion containing the solubilized oil to lower the viscosity of the micellar dispersion to about 30 to about 1,000 cp. at ambient temperature. 